01 - Whip heavy cream with powdered sugar and vanilla extract in mixing bowl until stiff peaks form. Set aside.
02 - Toss blueberries with granulated sugar if desired. Let sit for 10 minutes to release juices.
03 - Arrange half of cake cubes in even layer at bottom of trifle dish or glass bowl.
04 - Spread half of lemon curd evenly over cake cubes.
05 - Scatter half of blueberries over lemon curd layer.
06 - Spread half of whipped cream over blueberries.
07 - Layer remaining cake cubes, lemon curd, blueberries, and whipped cream in same order.
08 - Sprinkle lemon zest over top and add extra blueberries for decoration.
09 - Refrigerate for at least 1 hour before serving to allow flavors to meld and texture to set.